Air cleaner assemblies are widely utilized in connection with intake air flow, for example to internal combustion engines. Air cleaners are used on such equipment as: heavy duty trucks; construction equipment, (for example, graders, bulldozers, and backhoes); agricultural equipment (for example, tractors and combines); off-road vehicles; buses; light duty trucks; automobiles; special equipment (for example, forklifts and loaders); and other types of equipment (for example, lawn tractors). The engines for such systems generally use an air cleaner, which may vary in size and capacity, depending on the system. For systems generally utilizing an 8-inch air cleaner, the engines are typically about 5 liters and have a horse power of typically about 100 hp.
A purpose of the air cleaner, in such systems, is generally to filter incoming air to the engine, in order to protect engine parts from damage. In general, the air cleaners comprise housings having removable and replaceable filter elements positioned therein. The filter elements in many systems have generally circular or cylindrical configurations and are operated in a "forward flow" manner; i.e., with filtering flow from an exterior of the element to an interior. For equipment of the type described above, often the air flow rates through the air cleaners are the order of about 30 to 350 CFM (cubic feet per minute) (about 0.8-10 cubic meters per minute), depending on whether the engines are idling or under load. To accommodate the desired filter lifetime, filter efficiency needs and space limitations, generally filter element diameters on the order of 3.0 to 8.5 inches (about 75-210 mm) are commonly used with such equipment. Such filter elements generally weigh from 200 grams to 1200 grams new (clean), and can gain in weight by up to 3 times or more during use. Air cleaner housings having diameters of at least 4 to 10 inches (about 100-1000 mm), and lengths of 7.5 to 24 inches (about 100-600 mm), for such equipment, are relatively common. It is for use with such air cleaners as the ones described in this and the previous paragraph that arrangements according to the present invention were particularly developed. That is, the invention is particularly suitable for such systems, although it may be applied to others.
Air cleaners of the type described in the previous two paragraphs are regularly and routinely serviced. In some instances, air filter elements are removed and are either cleaned or replaced. Also, in some instances the interior chamber of the air cleaner is cleaned of materials such as leaves, settled dust, etc. To facilitate installation and servicing, air cleaner arrangements are constructed so that they can be opened and elements can be installed and removed.
Typically, to facilitate assembly and service, air cleaner housings are constructed in two major portions: a main body member section; and, a cover. Generally, the cover is non-threadably mounted on the body section, to enclose the air cleaner body. A variety of arrangements have been used to secure the cover to the housing, in air cleaners of the type characterized above, including, for example: bolt systems; metal latches; and plastic latch arrangements.